Rapid browning and drying processing method of Zihui papaya

Abstract

The invention discloses a rapid browning and drying processing method of Zihui papaya, and belongs to the technical field of traditional Chinese medicinal material processing. The method comprises the following steps: pretreating fresh pawpaw, cutting the pretreated pawpaw in half, and freezing the pawpaw at-10--20 DEG C for not less than 24 hours; then drying at 44-46 DEG C for 8-16 hours, heating to 54-56 DEG C, drying for 8-16 hours, and sealing and standing for 3-6 hours after drying; and then steaming at normal pressure for 1-2 hours, drying at 60-70 DEG C for 6-8 hours, and repeatedly steaming for 1-3 times to obtain a finished product. By adopting the method disclosed by the invention, the pawpaw processing time can be shortened to 4-7 days, and the obtained dry Zishi pawpaw product has the advantages of amaranth or reddish brown outer surface, reddish brown pulp, sunken central part, hard quality, faint scent smell, sour taste, stable quality, good color consistency and high oleanolic acid content.

Description

Technical Field

[0001] The invention belongs to the technical field of Chinese medicinal material processing, and specifically relates to a processing technology of Ziqiu papaya medicinal material, and in particular to a rapid color change technology during the processing of Ziqiu papaya. Background Art

[0002] Ziqiu papaya is derived from the dried nearly mature fruit of Chaenomeles speciosa (Sweet) Nakai., a plant of the Rosaceae family. Papaya fruit mainly contains malic acid, tartaric acid, ascorbic acid, oleanolic acid, ursolic acid, as well as flavonoids, tannins, saponins and other ingredients. Ziqiu papaya is mainly produced in Changyang County, Yichang City, Hubei Province. It has a long history of cultivation and is characterized by "few seeds, bright color, and wrinkled skin". It is a famous local medicinal material in my country. The intrinsic quality of Chinese medicinal materials, that is, the content of effective ingredients in Chinese medicinal materials, directly affects the quality of Chinese medicinal materials, their decoction pieces and Chinese patent medicines. The origin and processing of medicinal materials are one of the important factors affecting the intrinsic quality of medicinal materials. However, at present, Ziqiu papaya has always adopted the traditional fresh-cut sun-dried processing technology, that is, the fresh papaya after picking is directly cut in half and placed outdoors for sun drying. During the sun drying process, purple wrinkles will gradually appear on the papaya skin, and the color of the flesh will gradually deepen. The processing takes more than one month and is easily affected by rainy weather, resulting in unstable product quality.

[0003] The requirements for Ziqiu papaya in the Ziqiu papaya group standard "Authentic Medicinal Materials - Part 154: Ziqiu papaya" (T / CACM 1020.154-2019) and the Chinese Pharmacopoeia are "purple-red or reddish brown on the outer surface, reddish-brown flesh, concave in the center, hard, fragrant, and sour". According to research, the content of polyphenols in wrinkled papaya is about 1%. The browning of papaya skin and flesh includes enzymatic browning and non-enzymatic browning. Enzymatic browning is mainly caused by the participation of polyphenol oxidase and other enzymes with polyphenol components as substrates; non-enzymatic browning is mainly caused by the oxidation of polyphenols, which may also involve the Maillard reaction. Both enzymatic browning and non-enzymatic browning require contact between substrates and oxidizing substances. The traditional papaya processing technology (fresh-cut and sun-dried) has two parallel paths of drying dehydration and browning. The early stage is mainly enzymatic browning, and the later stage is mainly non-enzymatic browning. This traditional process has the problems of long papaya discoloration time and unstable product quality. Summary of the invention

[0004] In view of the problems of long color change time and unstable product quality in the existing Ziqiu papaya processing process, the object of the present invention is to provide a rapid color change technology in the Ziqiu papaya processing process that meets the requirements of the pharmacopoeia.

[0005] In order to achieve the above technical objectives, the inventors improved the process by combining freezing technology + steaming technology + intermittent heat pump drying technology, thereby solving the problems of long discoloration time and unstable product quality in the traditional papaya preparation process.

[0006] Specifically, the object of the present invention is achieved by: a method for accelerating the browning and drying of Ziqiu papaya, the method comprising the following steps:

[0007] (1) Clean the surface dust of fresh papaya, remove the insect-infested parts, cut it in half, and freeze it at -10 to -20°C for no less than 24 hours;

[0008] (2) placing the papaya treated in step (1) in a heat pump drying device, drying at 44-46° C. for 8-16 hours, then heating to 54-56° C. for 8-16 hours, controlling the humidity of the hot air at 20%-30% during the drying process, and sealing and standing for 3-6 hours after drying;

[0009] (3) steaming the papaya treated in step (2) at normal pressure for 1 to 2 hours, placing it in a heat pump drying device after steaming, and drying it at 60 to 70° C. for 6 to 8 hours, and controlling the humidity of the hot air to 20% to 30% during the drying process;

[0010] (4) Repeat step (3) 1 to 3 times to obtain the finished product.

[0011] It should be noted that the technical concept of the present invention is that the membrane permeability of papaya can be changed by freezing treatment, so that the substrate polyphenols and enzymes can react quickly, while steaming and heat pump drying can promote non-enzymatic browning. The application of this technology can shorten the processing time of papaya to 4-7 days, and the product test results show that the product quality is better than traditional processed products.

[0012] Further preferably, in the method for accelerating the browning and drying of Ziqiu papaya as described above, the equipment for freezing treatment in step (1) is a refrigerator or a freezer.

[0013] Further preferably, in the method for accelerating the browning and drying of Ziqiu papaya as described above, the parameters of the freezing treatment in step (1) are: freezing at -10 to -15°C for 24 to 48 hours.

[0014] Further preferably, in the method for accelerating the browning and drying of Ziqiu papaya as described above, the parameters of the drying treatment in step (2) are: drying at 45°C for 8 to 12 hours, then heating to 55°C and drying for 12 to 16 hours, and controlling the hot air humidity at 20% to 25% during the drying process.

[0015] More preferably, in the method for accelerating the browning and drying of Ziqiu papaya as described above, the time for the steaming treatment in step (3) is 1 to 1.5 hours.

[0016] Further preferably, in the method for accelerating the browning and drying of Ziqiu papaya as described above, the parameters of the drying treatment in step (3) are: drying at 60-65° C. for 6-8 hours, and controlling the hot air humidity at 20%-25% during the drying process.

[0017] Compared with the prior art, the rapid browning and drying processing method of Ziqiu papaya provided by the present invention has the following advantages and progress:

[0018] (1) The Ziqiu papaya dried product processed by the method of the present invention has stable quality and good color consistency;

[0019] (2) The dried Ziqiu papaya obtained by the method of the present invention has a high oleanolic acid content of 0.6-0.7%;

[0020] (3) The dried Ziqiu papaya product processed by the method of the present invention has a purple-red or red-brown outer surface, a red-brown flesh, a concave center, a hard texture, a fragrant smell, and a sour taste;

[0021] (4) The method of the present invention shortens the processing time of papaya to 4-7 days, and the equipment used is simple and can be found in the production area, with low energy consumption and can be applied on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Actual pictures of the color changes of papaya during processing; (a) fresh papaya; (b) baked once; (c) steamed once; (d) baked twice.

[0023] Figure 2 To investigate the effect of steaming times on the oleanolic acid content in papaya.

[0024] Figure 3 Effect of different drying temperatures on the oleanolic acid content of papaya. DETAILED DESCRIPTION

[0025] The present invention is further illustrated by the following examples. It should be understood that the preparation methods of the embodiments of the present invention are only used to illustrate the technical scheme and technical effects of the present invention, rather than limiting the scope of protection of the present invention, and simple improvements to the preparation methods of the present invention under the premise of the overall concept belong to the scope of protection claimed by the present invention.

[0026] Embodiment 1:

[0027] 1) Papaya raw material processing: After receiving the fresh papaya, clean the surface dust, remove the insect-eaten parts, and then cut it in half;

[0028] 2) Freezing: Freezing the papaya obtained in step 1) at -10°C for 24 hours;

[0029] 3) Drying: Place the papaya obtained in step 2) in a heat pump drying device, dry at 45° C. for 12 h, then heat to 55° C. and dry for 16 h. During the drying process, the humidity of the hot air is controlled at 20%. After drying, seal and let stand for 4 h;

[0030] 4) Steaming: steam at normal pressure for 70 minutes;

[0031] 5) Secondary drying: After steaming, heat pump drying is performed for 8 hours at a temperature of 60°C and a humidity of 20%;

[0032] 6) Second steaming: Same as the first steaming conditions, after steaming, dry according to the second drying conditions until the moisture content is <15%.

[0033] The obtained product is reddish brown, the flesh is reddish brown, the center is concave, the texture is hard, and it has a fresh fragrance. The oleanolic acid content is about 0.55-0.7%.

[0034] Embodiment 2: Same as embodiment 1, except that:

[0035] 2) Freezing: Freezing the papaya obtained in step 1) at -20°C for 48 hours;

[0036] 3) Drying: Place the papaya obtained in step 2) in a heat pump drying device, dry at 45° C. for 16 hours, then heat to 55° C. and dry for 8 hours. During the drying process, the humidity of the hot air is controlled at 25%. After drying, seal and let stand for 6 hours;

[0037] 4) Steaming: steam at normal pressure for 90 minutes;

[0038] The obtained product has purple-red skin, reddish-brown flesh, a sunken center, hard texture, a fresh fragrance, and an oleanolic acid content of 0.5-0.6%.

[0039] Embodiment 3: Same as embodiment 1, except that:

[0040] 1) Papaya raw material processing: After receiving the fresh papaya, clean the surface dust, remove the insect-eaten parts, and then cut it in half;

[0041] 2) Freezing: Freezing the papaya obtained in step 1) at -15°C for 36 hours;

[0042] 3) Drying: Place the papaya obtained in step 2 in a heat pump drying device, dry at 45° C. for 8 h, then heat to 55° C. and dry for 16 h. During the drying process, control the humidity of the hot air to 30%. After drying, seal and let stand for 3 h;

[0043] The obtained product has a reddish brown outer skin, reddish brown flesh, a sunken center, a hard texture, a fresh fragrance, and an oleanolic acid content of 0.55-0.63%.

[0044] Embodiment 4: The same as embodiment 1, except that it further comprises the following steps:

[0045] 7) Steaming again: Steam again once, using the same method as steps 4) and 5).

[0046] The obtained product has purple-red skin, brown flesh, a sunken center, hard texture, a fresh fragrance, and an oleanolic acid content of 0.49-0.54%.

[0047] Embodiment 5: The same as embodiment 1, except that it further comprises the following steps:

[0048] 7) Re-steaming: Due to differences in the maturity of raw materials, if the product color is not enough, it can be steamed again 2-3 times until it meets the requirements.

[0049] The obtained product has purple-red skin, brown flesh, a sunken center, hard texture, a fresh fragrance, and an oleanolic acid content of 0.47-0.58%.

[0050] The following are some examples of failed tests experienced during the test:

[0051] Comparative Example 1: Same as Example 1, except that:

[0052] 3) Drying: The papaya obtained in step 2) is placed in a heat pump drying device and directly dried at 60° C. for 16 h. During the drying process, the humidity of the hot air is controlled at 20%. After drying, the papaya is sealed and left to stand for 4 h.

[0053] The product obtained in comparative example 1 is reddish brown, the flesh is reddish brown, the texture is hard, and the appearance color is uneven. The reason for the failure is that the drying process is a process in which the internal moisture diffuses from the inside to the outside. Direct high-temperature drying of fresh fruits will cause the epidermis to lose water quickly and form a hard shell. The internal moisture has a long diffusion distance, and the epidermis cannot diffuse out after forming a hard shell, which affects the drying efficiency.

[0054] Comparative Example 2: Same as Example 1, except that:

[0055] 2) Freezing: Freezing the papaya obtained in step 1) at -5°C for 10 hours;

[0056] The problem with the product obtained in Comparative Example 2 is that the color difference between different individuals is large. The reason for the failure is that papaya contains organic acids, sugars and other ingredients, so its freezing point is low, and the freezing temperature of -5°C is not enough to completely freeze the papaya, which affects the subsequent processing effect.

[0057] Comparative Example 3: Same as Example 1, except that:

[0058] 4) Steaming: steam at normal pressure for 30 minutes;

[0059] Comparative Example 3 has a short steaming time and a slow color change.

[0060] Comparative Example 4: Same as Example 1, except that:

[0061] 4) Steaming: steam at normal pressure for 150 minutes;

[0062] The product obtained in Comparative Example 4 had a dark red skin, purple flesh, a burnt smell, and a content of oleanolic acid, an effective ingredient, between 0.43% and 0.51%, which was not up to standard.

[0063] Comparative Example 5: Same as Example 1, except that:

[0064] 3) Drying: placing the papaya obtained in step 2) in a heat pump drying device, drying at 45° C. for 12 h, then heating to 55° C. for 16 h, controlling the humidity of the hot air at 20% during the drying process, and leaving the device to stand without sealing after drying;

[0065] The products obtained in comparative example 5 had color differences between individual products and poor appearance. The reason for the failure was that the closed static process was a process of rebalancing the moisture inside and outside the papaya, which was conducive to uniform color. Omitting the closed static process would cause uneven product color.

[0066] The reasons for the above failed test examples are insufficient steaming or drying time, or over-steaming, etc. Combining the above embodiments and comparative examples, it can be seen that the means of promoting papaya browning in the present invention mainly promotes enzymatic browning and non-enzymatic browning, and the two work together to achieve the effect of rapid color change. Therefore, the present invention solves the problem of long processing time of Ziqiu papaya using traditional technology and solves the difficulties in the industry.

Claims

1. A method for accelerating the browning and drying of Ziqiu papaya, characterized in that: The method comprises the following steps: (1) Clean the surface dust of fresh papaya, remove the insect-infested parts, cut it in half, and freeze it at -10 to -20°C for no less than 24 hours; (2) placing the papaya treated in step (1) in a heat pump drying device, drying at 44-46° C. for 8-16 hours, then heating to 54-56° C. for 8-16 hours, controlling the humidity of the hot air at 20%-30% during the drying process, and sealing and standing for 3-6 hours after drying; (3) steaming the papaya treated in step (2) at normal pressure for 1 to 2 hours, placing it in a heat pump drying device after steaming, and drying it at 60 to 70° C. for 6 to 8 hours, and controlling the humidity of the hot air to 20% to 30% during the drying process; (4) Repeat step (3) 1 to 3 times to obtain the finished product.

2. The method for accelerating the browning and drying of Ziqiu papaya according to claim 1, characterized in that: The equipment for the freezing treatment in step (1) is a refrigerator or a freezer.

3. The method for accelerating the browning and drying of Ziqiu papaya according to claim 1, characterized in that: The parameters of the freezing treatment in step (1) are: freezing at -10 to -15°C for 24 to 48 hours.

4. The method for accelerating the browning and drying of Ziqiu papaya according to claim 1, characterized in that: The parameters of the drying treatment in step (2) are: drying at 45° C. for 8 to 12 hours, then heating to 55° C. for 12 to 16 hours, and controlling the hot air humidity at 20% to 25% during the drying process.

5. The method for accelerating the browning and drying of Ziqiu papaya according to claim 1, characterized in that: The steaming time in step (3) is 1 to 1.5 hours.

6. The method for accelerating the browning and drying of Ziqiu papaya according to claim 1, characterized in that: The parameters of the drying treatment in step (3) are: drying at 60-65° C. for 6-8 hours, and controlling the hot air humidity at 20%-25% during the drying process.

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